Wireless communication systems today typically operate in spectrum that is either dedicated for each individual system, e.g. mobile networks in block-licensed IMT spectrum, or shared among several, similar systems on an equal-access basis, e.g. Wi-Fi and Bluetooth in license-exempt RLAN/ISM spectrum. Other forms of sharing also exist to a limited extent, e.g., defined by static, geographical exclusion zones.
New forms of sharing are discussed today, including wireless communication system sharing spectrum with one or more radar systems. For example, in the United States the Federal Communications Commission, FCC, is planning to release the 3.5 GHz band (3550 to 3650/3700 MHz) on a nation-wide, shared basis with Department of Defense's existing usage of ship-borne radars used for purposes such as Missile and Gunfire Control, and Long-Range Surveillance and Aircraft Carrier. The conditions of use for (commercial) wireless communications systems will require them to stop transmissions that could interfere any radar currently using the band. Since the radars are ship-borne the set of potentially interfering communications system transmitters can vary when the radar changes its location, particularly if the transmitters are deployed over a large coastal area, as schematically illustrated in FIGS. 1 A-B.
For example, such sharing may be managed by a separate Spectrum Access System, SAS, that can include database functionalities to facilitate handling of when and where radar protection is needed. However, for national security reasons it may not be possible for a SAS to handle information about radar usage.